Abstract: The present invention relates to treating a medium and more particularly to treating a medium to reduce or inhibit biofouling.The invention provides a method for the reduction or inhibition of biofouling of a part of a system which is subject to contact with a medium capable of causing biofouling by providing biological material. The method comprises contacting the medium with a support material (which is preferably a high surface area material) so as to cause biological material to form on the support material in preference to the part of the system.The invention may be applied, for example, to inhibit or reduce biofouling of heat transfer surfaces in cooling water systems.

Abstract: A process for hardening the surface of a metal body in which the surface is first bombarded with ions capable of occupying interstitial sites in its crystal lattice, then a coating of a reactive metal is deposited on the surface, and finally the coating is bombarded with ions which will react with it to form a hard material such as a carbide or nitride. The bombardment is continued until the hard material has become embodied in the surface by means of radiation enhanced diffusion.

Abstract: A porous electrically conducting filter, e.g. a membrane for filtration equipment, is cleaned by setting up an electrochemical cell comprising the membrane as a first electrode (usually the cathode), a second electrode, and an electrolyte capable of being electrolyzed to a gaseous product at the first electrode. When a potential is applied across the cell, the gaseous product of electrolysis (e.g. in the form of microbubbles) cleans the surfaces of the membrane by forcing foulant material therefrom.The electrolyte is constituted by the liquid being filtered (with the possible addition of a salt to increase electrical conductivity, if necessary) thus enabling filter cleaning to be carried out in situ while the liquid being filtered continues to be passed through the filter.

Abstract: A manipulator arm consisting of a plurality of annuli joined together by lengths of tubing having circumferential corrugations, two longitudinal webs extending the length of the manipulator arm and diametrically spaced with respect to the annuli, the webs being adapted to be flexible in a first plane but stiff in a second plane at right angles to the second plane, and so positioned that the first planes of the webs are coincident thereby to render the manipulator arm flexible in the first plane but stiff in the second plane, and means for causing the manipulator arm to flex in the first plane.

Abstract: A method and an apparatus are provided for the production of a layer of a metallic material by deposition from the vapor phase onto an exposed surface of a collector. The exposed surface is maintained at a desired temperature by passing a heat transfer liquid through ducts within the collector and controlling the temperature of the liquid in accordance with the thickness of the deposited layer.

Abstract: During treatment of a specimen (10) in an evacuated chamber, the temperature of the specimen is controlled by varying the radiant heat flux to and from the specimen. The specimen is supported adjacent to but spaced apart from a heat sink (14) with a blackened surface (16), and between the specimen (10) and the heat sink (14) are one or more reflective elements (20) movable so as to cover a larger or a smaller fraction of the surface of the heat sink.

Abstract: A continuous flow electrophoretic separator 10 comprises a cylindrical stator 12 and a tubular rotor 14 defining an annular chamber 28 therebetween, through which a carrier liquid 44 is passed and in which electrophoresis of a migrant material injected into the carrier liquid 44 takes place. An inlet for the migrant material is defined within the stator 12 and comprises a supply duct 34, a first annular chamber 140, a second annular chamber 144, a peripheral slot 150, ducts 134 providing communication between the supply duct and the first chamber, and channels 142 providing communication between the first chamber and the second chamber. Migrant material flows from the second chamber through the slot to emerge uniformly into the carrier liquid as a well defined narrow layer.

Abstract: A heat pipe stablized specimen container for irradiation of specimens at substantially constant temperature within a liquid metal cooled fast reactor comprises a heat pipe containing a vaporizable substance such as sodium. The container is of double-walled construction with the gap filled with argon and at top of the container a volume of argon is trapped within a cavity of the liquid metal level within the container in such a way that retention of argon in this zone is not dependent on sealing welds in the structure of the container, the argon blanket in this zone affording thermal insulation at the top of the container and also around part of the heat pipe, viz an adiabatic section of the latter.

Abstract: A continuous flow electrophoretic separator (10) is provided, comprising a cylindrical stator (12) and a concentric tubular rotor (14), and electrode systems (24, 26) incorporated into the stator and the rotor defining between them an annular separation chamber (28). One or both electrode systems include a tubular semi-permeable membrane (56) supported by a support tube (58) of a rigid plastics material and grooved on its inner and outer surfaces. The grooves (64, 62) are deep enough to provide fluid communication between the two surfaces of the support tube, and those grooves (64) adjacent to the separation chamber are preferably less than 3 mm wide. If the membrane (56) is between the support tube (58) and the separation chamber (28), then the support tube (58) may have both longitudinal (60) and circumferential grooves (64) adjacent the membrane, and longitudinal grooves (62) on its other surface.

Abstract: An aerodynamic window for a gas laser, comprising a chamber positioned at one end of a structure forming part of a laser cavity in which lasing action can take place the chamber having first and second apertures aligned with the optical axis of the laser cavity and its longitudinal axis at an acute angle to the optical axis of the optical cavity and means whereby the chamber can be continuously evacuated, wherein the chamber is of uniform cross section and the apertures are situated in a side wall and an end wall of the chamber respectively.Preferably, the second aperture is displaced from the longitudinal axis of the chamber towards the first aperture.

Abstract: An ultrasonic probe for inspecting a weld between a cylinder (C) and a pipe (P) is caused to move in a holder at the end of an arm (11) pivoted at a point on the axis (Z) of the pipe so that the line (12) of transmission from probe penetrates the weld and, when projected beyond the weld, intersects the axis (Z) of the pipe (P) for all positions of the arm.

Abstract: An electric power transfer system in the form of a transformer comprises a first core portion 12 with two or more regions 14, and a second core portion 34 movable relative to the first core portion 12 and providing a low reluctance flux path between the regions 14. Primary windings 10 are wound around the first portion 12 of the core, and secondary windings 20 wound around the second portion 34. The regions 14 may extend along a path along which power is to be supplied, and that path may be straight, curved or circular.

Abstract: The present invention relates to compounds and more particularly to cerium compounds and cerium compounds in association with other elements.The invention provides a process for the preparation of a dispersible product containing a cerium compound which comprises heating a cerium (IV) oxide hydrate in the presence of a salt to cause deaggregation of aggregated crystallites in the cerium (IV) oxide hydrate and produce a dispersible product containing a cerium compound.The salt may be chosen such that a selected chemical element is present in the dispersible product.

Abstract: A fluidic pumping system comprises a reverse flow diverter positioned below the level of a liquid to be pumped and inserted between a charge vessel and a delivery pipe. A control system including pressure-responsive devices effects alternate pressurizing and venting of the charge vessel for pumping the liquid. Passage of liquid from the charge vessel into pipes leading to a compressed air supply and the reverse flow diverter generates pressure changes which are detected and the electric output signals are used to operate the control means.

Abstract: An ice detector to detect a lyaer of ice on a thin solid sheet 14, such as the skin of an aircraft wing, even in the presence of water, comprises two ultrasonic transducers attached to the sheet. The first transducer 10 is adapted to cause propagation of ultrasonic waves through the sheet 14 having their predominant component parallel to the surface of the sheet 14. Such waves will dissipate energy into an ice layer adhering to the surface, but not into air or a liquid layer. The second transducer 30 is adapted to detect the waves propagating in the sheet and to give a signal representative of their amplitude. A discriminator 34 responsive to the signal detects the presence of an ice layer on the surface.

Abstract: In the repair of a leaking heat exchanger tube (10) with a repair tube (11) at a braze (12), strain in the exchanger tube (10) is relieved during the brazing operation. Where the exchanger tube is of U-shape both legs (10A and 10B) are treated similarly. Strain relief could also be obtained by a thinning and bulging operation in the exchanger tube at a region which also receives heat from the brazing operation so, on brazing, yield takes place at the bulge.

Abstract: The production of a reaction-bonded silicon carbide artefact by siliconizing a green body comprising a coherent mixture of carbon and silicon carbide particles includes the step of forming a layer of carbon of open cellular structure on the green body by carbonization of a sleeve or tube on the green body by carbonization of a sleeve or tube of carbonaceous material in contact with the body. This material may be impregnated with particulate silicon suspended in water or a paste. The material may be a quilted or woven fabric of fibrous material or it may be in the form of paper. The material is in a flexible strip or sheet form to enable it to be wrapped around the green body or a former about which the green body is to be formed.

Abstract: An electrochemical extraction method comprises establishing a cell of the form working electrode: flowing aqueous electrolyte solution: second electrode. The working electrode includes an ion exchange material and the second electrode may include ion exchange material. D.C. potential is applied to the cell to adsorb ions onto the working electrode and cell polarity is subsequently reversed to elute the adsorbed ions.The cell is separated by a cell divider, e.g. in the form of an ion selective membrane, into first and second electrolyte compartments and the solution is passed through the compartment adjacent the working electrode to effect adsorption and, where the second electrode includes ion exchange material, solution is passed through the compartment adjacent the second electrode to effect desorption.

Abstract: Some forms of corrosion, and inter-granular attack in particular, occur without significantly altering the bulk dimensions of the body attacked. Where elastic properties are changed, this is detected by a sensitive ultrasonic inspection based upon the resonant frequency or frequencies with which the ultrasonic signals reverberate within the body. Resolution is improved by gating out the first, top, surface reflection and by swept gain control through the gating period.

Abstract: A machine for dismantling, unloading and transferring to a disposal facility, nuclear reactor structure and/or components, which have been irradiated during operation of the reactor. The machine includes in one example a gantry mounted on a rigid, undismantled part of the reactor such as rails on the refuelling level of the reactor, a carriage angularly movable on the gantry, a platform movable linearly on the carriage, a mast on and axially movable relative to the platform, a manipulator mounted on the mast for angular and linear movement relative thereto, a variety of tools selectively mountable on the manipulator for effecting dismantling of reactor structure and/or components, and hoist means movable along a beam rotatable about the reactor center line and alignable with other beams to allow transfer of the hoist means from one beam to another. Alternative arrangements for varying the elevation of the mast are also disclosed.